Hello I have a question on angular velocity

[tinothynguyen]

1. Here is the equation http://i.imgur.com/EKdWnws.png

2. The attempt at a solution
The first part I've done correctly. So here's my thought process:
To get the period I used T=2 * pi * sqrt(r3 /GM_E)
T=5521s
W(angular velocity)=2pi/T
W=1.138*10-3 rad/s
V=WR where r is 6754000m
V=7686m/s
Since the thrusters double the speed of the satellite v will be become twice that and the radius will be 15.9% more. Therefore:
2V=W(R+R*15.9/100)
Substituting in all the values I had to get W my answer was 1.964*10-3 rad/s.
But I didn't get my answer right. I may have done the wrong process but it seems pretty logical from my perspective. Please enlighten me.

 

[Orodruin]

The equation v = ωr is only valid for the tangential velocity (or the total velocity if the radial component is zero). After the craft has doubled its velocity, it will no longer have a circular orbit. You also cannot assume that the velocity will be constant with radius.

To help you along: Do you know of any conservation laws that may be applicable?

 

[tinothynguyen]

Can't really think of one. The only ones I know of are energy and momentum laws.

 

[Orodruin]

So, the question becomes: Which momentum is conserved, linear or angular?

 

[tinothynguyen]

I would say angular?

 

[Orodruin]

That is a good start. So what expressions do you know that give the angular momentum? What is the initial angular momentum?